Brinkman's law as $Γ$-limit of compressible low Mach Navier-Stokes equations and application to randomly perforated domains
Peter Bella, Friederike Lemming, Roberta Marziani, Florian Oschmann
TL;DR
The paper establishes a Γ-type limit for time-dependent compressible Navier–Stokes equations in the low Mach regime on families of domains $Ω_ε$ that Mosco-converge to a fixed domain $Ω$, proving convergence to the incompressible Navier–Stokes–Brinkman system with a Brinkman term $μM\mathbf{u}$ when a strong limit solution exists. The authors develop a robust framework based on finite energy weak solutions, dissipative limits, energy inequalities, and a relative energy method to derive incompressibility, pass to the limit in the momentum equation, and prove weak–strong uniqueness. A key contribution is the treatment of the critical perforation regime ($α=3$) which introduces the Brinkman drag in the limit, extending prior stationary results to the time-dependent setting. They further apply the theory to randomly perforated domains, showing stochastic homogenization results where the holes are Poisson distributed with radii of order $ε^{3}$, and provide the necessary construction of test functions via Allaire-type corrections. The work provides a rigorous bridge between Brinkman-type drag in porous media and the low Mach limit of compressible flows, with implications for stochastic homogenization in random porous architectures.
Abstract
We consider the time-dependent compressible Navier-Stokes equations in the low Mach number regime inside a family of domains $(Ω_\varepsilon)_{\varepsilon > 0}$ in $\mathbb{R}^3$. Assuming that $\lim_{\varepsilon \to 0} Ω_\varepsilon = Ω\subset \mathbb{R}^3$ in a suitable sense, we show that in the limit the fluid flow inside $Ω$ is governed by the incompressible Navier-Stokes-Brinkman equations, provided the latter one admits a strong solution. The abstract convergence result is complemented with a stochastic homogenization result for randomly perforated domains in the critical regime.
